


Taught Why Now the Mighty Mass of Water Swells

by akathecentimetre



Series: A Gentleman's Agreement [12]
Category: Rivers of London - Ben Aaronovitch
Genre: Agreements, F/M, M/M, Mermaids, Scotland, Selkies, Water, magical research
Language: English
Status: Completed
Published: 2017-10-16
Updated: 2017-10-16
Packaged: 2019-01-17 17:21:18
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 6,897
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12370410
Author URL: https://archiveofourown.org/users/akathecentimetre/pseuds/akathecentimetre
Summary: "I've suddenly decided I don't want to," I announced.The black waters of Loch Nell were keeping remarkably mum about my reticence as I stared down at them from the edge of the dock. The very deep, very dark, extremely perhaps life-threateningly cold waters of Loch Nell, as my brain saw fit to add. In December. In northern Scotland. Because maybe monsters.





	Taught Why Now the Mighty Mass of Water Swells

**Author's Note:**

> Thanks to [Zoya1416](https://archiveofourown.org/users/Zoya1416/pseuds/Zoya1416) for the prompt of water rescues! I hope you enjoy this :-) It's an extra-canon piece - I haven't thought too hard about exactly where in canon it sits - and it's from Peter's POV.

*

**2015**

"I've suddenly decided I don't want to," I announced.

The black waters of Loch Nell were keeping remarkably mum about my reticence as I stared down at them from the edge of the dock. The very deep, very dark, extremely perhaps life-threateningly cold waters of Loch Nell, as my brain saw fit to add. In December. In northern Scotland. Because maybe monsters.

We were so fucked.

It had started in about mid-November when we'd received a call from a rather confused-sounding PC Dickon, whose beat covered several places I'd never heard of in the Western Highlands. One of said places turned out to be Strontoiller – a place which barely qualified to be called a hamlet, as far as Google could show me – where a young man who had probably just been out on the lash had come home one early morning soaking wet and babbling about mermaids.

It probably wouldn't have gone any further than that had PC Dickon not sent photographs of some odd bitemarks on the victim's leg to his sergeant, who sent them to his inspector, who sent them off to a superior in Glasgow, who made one too many connections on HOLMES to reports of other young drunken men who had also come home babbling about mermaids and promptly sent it all back down the line with an instruction to PC Dickon to call 'Falcon' and leave him the hell out of it. PC Dickon himself, once he found the Folly's phone number, sounded rather aggrieved with himself and the whole sorry mess of them for giving even a fraction of a toss, and like he just wanted to go to bed.

I, of course, had then made the mistake of thinking that it couldn't hurt to take an hour, on a chilly, grey morning when I certainly didn't want to be working on my Latin, to check it out. Three hours later, with my feet under Toby like he was an electric blanket, I had discovered almost fifteen registered cases in the previous decade of public disorder, drunkenness, or petty assault in the general area of Loch Nell which included variants of the statement 'Something Bit Me,' and decided I would – somewhat reluctantly – have to call in the big guns.

"Hm," Nightingale said as he peered over my shoulder at my initial compilation in HOLMES. "Rather too much for a coincidence."

"Maybe," I said. "But it could keep?"

"Scotland is lovely at this time of year," Nightingale said, somewhat tonelessly. When I raised an eyebrow at him, he at least had the decency to look sheepish about it. "I was strictly instructed in this matter by the rather formidable Mrs. Wilson. Charming woman."

"Old teacher?"

"Abdul's mother," Nightingale sighed, and it was really, incredibly difficult for me in that moment not to giggle. "You're right, it could probably keep. But I would also suspect that once a call is made to Falcon, someone is going to notice."

And so it proved to be, because it only took two days for Seawoll to text me, managing to convey that he was incredibly pissed off in incredibly few characters, to ask why he was getting calls from Oban about why no one had come north to sort out their selkie problem.

In the end, it took nearly two weeks to put the traveling circus together: me, Nightingale, Dr Walid (whose ears had audibly perked up on the phone when we mentioned Scotland, and who promptly managed to find us a cottage in the area that we could borrow from an old school friend), Beverley (because river goddesses could probably translate mermaid, right? though she didn't take it well at first), and Sahra Guleed, who was tacked on at the end by Seawoll when he realized someone from the regular Met would need to be on board to make sure the lines of who could be blamed for what were as clear as possible if anyone were to cork it.

Bev, Sahra and I started driving early on December 2nd in the Asbo, following Nightingale and Walid in the Jag as it serenely swooped its way between lanes on the M6. It was to be a long and boring trip to the bay of Oban, punctuated by stops at Little Chefs, Beverley fiddling with the radio, and Sahra snoring, surprisingly loudly, in the back seat. Somewhere around Glasgow, with more than two hours still to go, Beverley looked like she was about to attempt a game of footsie to perk us both up, but that got Sahra leaning instantly in from the back, adjusting her hijab and scowling.

"You do realize there'll be none of that," she said, tapping us both firmly on our shoulders. "This isn't a holiday, and there shall be no shagging."

"But _cold_ ," I said grumpily. "Body heat. Huddling for warmth."

"Sod that," Sahra grinned. "If I hear any of the four of you up to anything tonight, I'm taking the Asbo back myself. Try enjoying _that_ ride in the Jag."

"Go on then," I protested. "I dare you to tell Nightingale and Walid that, too."

"Nuh-uh," Sahra said, shaking her head as she retreated into her nest. " _You_ I can at least tell off without getting sacked."

The cottage turned out to be a few miles south of Loch Nell and Oban, and looked nothing more than squat and ugly as we drove up to it in the dark (sunset that day in Scotland, as Beverley had told me multiple times with increasing amounts of frustrated desperation, had been at 3:40pm). But it was comfortable enough once we had gotten inside, all dark woods and thick carpet, its floorboards creaking in the corridors and the occasionally-flickering light fixtures giving off a warm yellow glow. It took Nightingale, Sahra and I close to forty-five minutes to get us all settled, given all the rooms which had to be opened and aired and all the luggage which had to be brought in from the cars, and needing to unpack the shopping Nightingale had stopped to get in Glasgow while we in the Asbo had still been making our way up from Gretna Green – which, somewhat to my surprise, included several bottles of the good stuff, which rather put paid to Sahra's notion that we weren't on some sort of extremely British vacation.

Dr Walid and Beverley had been bustling about the kitchen, tending to bubbling pots; at times, Walid hummed or quietly sang snatches of something lilting in a mix of English and Gaelic, whereas I was mostly preoccupied with how the low light and the way she was looking at me over her glass of wine did Beverley fantastic favors.

"That's a nice tune," I said as the beer I had pinched from Nightingale's haul took a bit of a hold and Abdul started plating up piles of steaming potatoes and stew. "What's it about?"

"Shagging in bushes," Walid said cheerfully, and laughed as he passed me my portion. "Don't look at me like that – it was arranged by Haydn. _Ith do shàth._ "

"Thanks?" I said, really quite bewildered now, and took my food through to the crooked dining room. The loud, chatty, strangely collegial meal which followed, with Nightingale smiling at the lot of us from the head of the table like some county manor patriarch, almost made me forget the fact that I was hours away from certain hypothermia, and was followed by after-dinner drinks in front of a roaring fire in the sitting room which ended with Sahra starting a minor row with Walid over _why_ exactly they had to perform the night prayer outside, and no, freezing to death was not character-building, so he could stop being so bloody upbeat.

"This was nice," Beverley yawned into my shoulder around midnight, when all the thick shutters of the cottage had been closed and the fire was crumbling into embers and we had retreated to a small bedroom upstairs which was just cold enough that you felt your cheeks sting anytime you put your face out from the edge of the layers of duvet. "Don't get yourself eaten tomorrow. You'd ruin it."

"You seem to be under the impression I have _any_ control over that," I complained, but she wasn't listening. Sahra had clearly made her point about the no-sex thing, so the only thing left to do was fall asleep and not dream about drowning to the best of my ability.

Which is how I ended up sitting on the ragged pier that extended out into Loch Nell, hundreds of yards from any farmhouse and many metres away from the parked Jag and Asbo with their god-given ability to create warm air, staring down into what would probably kill me. Beverley was bright-eyed and happy as she smelled the water, though we had decided she would stay on dry land to avoid angering any local denizens; Nightingale, in contrast, having towed a bag full of equipment down the dock, was looking grumpy in his tweed. He was also carrying a marine biologist's spear that Dr Walid had borrowed from one of his confusingly diverse set of friends, which would quickly and relatively painlessly jab any creature we encountered for the purposes of collecting a DNA sample. Sahra had been assigned the stopwatch to keep track of how long we were in the water, to guard against our body temperatures falling too low, and was bundled up in a puffy jacket, her hijab pulled tightly around her face.

I, meanwhile, had gone for the full James Bond villain look from _Thunderball_. I had insisted to Walid that I would need a wetsuit which covered every possible inch, and he had managed to provide: the suit was one enormous piece of double-thick neoprene, with fully articulated fingers and toes, and thankfully extended to cover my head and ears, leaving only my face uncovered. It had required a lot – maybe half an hour's worth – of quite embarrassing wriggling to get into, but given how I already couldn't feel the end of my nose just from being out in the early morning air I couldn't regret my choice no matter how much Bev had laughed at me or how many things I might have broken in the cottage as I flailed my way into it.

Walid, on the other hand, was wearing only a half-suit on the bottom and a swim cap, and looked unfairly trim and fit for his age as he sat next to me on the pier – I guessed he must have gotten into running or yoga in his middle years, or, knowing him, both. He also looked smug as hell, which just seemed unnecessary.

"Yeah, yeah, you probably grew up swimming in lochs every weekend, no need to rub it in," I grumbled, and proceeded to nearly have a fit as I dipped the tips of my toes in the water.

"I did, as it happens," Dr Walid said, grinning, and then he tilted sideways off the pier without further ceremony. He came back up a moment later, yelped something which sounded very rude indeed in Scots, and then reached up to take the DNA spear and a snorkel from Nightingale, wiping water from his eyes. "Best to get it over with, Peter," he said, not unkindly. "It'll hurt less if you do it all in one go."

"I hate this," I sighed, and, closing my eyes, took the plunge.

It really, _really_ hurt. I came back up spluttering and thinking I'd never be able to breathe again, and needed to clutch onto the pier in a most undignified fashion for a minute before I'd gotten over the shock. The water was dark and silent around me, and steam boiled out of my mouth across its surface.

"Why," I forced out eventually, "does – _anyone –_ live in Scotland?"

"Don't ask me, I left," Walid said from where he was treading water a few feet away; he tossed me a facemask and snorkel of my own, already rubbed with gelatin so they wouldn't fog up in front of my eyes, and then handed over a damp pair of flippers. "We'd better get moving. The faster we take a look, the faster we can get warm again."

Moving helped, though every muscle in my body was screaming that I should stay as still as possible so that no extra water molecules could touch me. It took a few fumbling moments for me to get my chattering teeth around the mouth of the snorkel and longer still for me to force myself to put my face back in the water, but once we had swum several metres away from the pier I sort of forgot about all of that, as well as the hovering group that was Nightingale, Beverley, and Sahra watching us.

It was hard to deny that the loch was beautiful. There was something eerie and perfect about how the sunlight, breaking through the clouds in patches, lanced downwards through the water towards the invisible bottom; there wasn't a fish or other animal to be seen, leaving it looking like we were floating through something endless.

After what felt like about a minute, with my muscles finally relaxing down from their cramp, the ghostly pale figure ahead of me that was Walid paused, and then, turning slightly, he pointed down into the murk off to our right, where there was a patch of water which looked a bit too haunted-house green to be natural in the dark. I gave him a thumbs up, and we struck out in the new direction.

They were around us suddenly. Webbed hands attached to a pair of smooth, freckled arms shot up out of the black and grabbed my shoulders, and water flooded into my snorkel with an unseemly gurgle as I was dragged down. It took a second for me to process the grey-green face that was suddenly right in mine: grinning, sharp-toothed, vaguely dog-like and clearly nasty.

Just as quickly as it had grabbed me, though, its grin gaped open wide and furious, and the claws on the ends of its fingers ripped partway through my wetsuit as it twitched away from me. The tip of the DNA spear was twisted in its side, and Dr Walid, clutching the other end of it with both fists, looked narrow-eyed up at us both.

I stared; four more of the mermaids, emerging from the gloom, converged on Walid like sharks. And then the water in my snorkel hit the back of my throat, and I choked, and my feet kicked me back up towards the surface on instinct. I broke into the air, took a breath, and immediately ducked back down, but all I could see was a tangled web of limbs sinking rapidly, and the DNA spear floating within my reach.

I grabbed it, turned tail, and swam as fast as I could for the pier, shouting at the top of what was left of my lungs.

"Sahra, stopwatch," I heard Nightingale say tightly as I approached; Sahra, her eyes wide and tense, clicked the timer off and on again, and it was the realization that she was now keeping track of how long Walid had been underwater that gave me the strength to haul myself up over the pier's edge.

"What were they?" Nightingale asked. He was pale and stone-like as he crouched down and looked me straight in the eye, every inch the shocked copper; the fact that it was Walid that was gone must have hurt like hell.

"No clue. Selkies, mermaids? Smooth skin, sharp teeth," I gasped. Sahra was putting a thick blanket around my shoulders, which didn't help against the cold in the slightest.

"Fuck this," Beverley said; she got down on her hands and knees and then onto her stomach on the pier, and then leaned forward far enough that her whole head went into the water. Whatever she was yelling under there didn't sound like English, but it did sound god-like, and made the surface of the lake tremble.

"Thirty seconds," Sahra said flatly.

There was a pause in Beverley's garbled shouting, and then a moment later she lifted her head up again, her soaked hair matted over her face like the girl from _The Ring_. "They say our leader needs to come down and negotiate."

"Tell them they will come up into the air," Nightingale said; he was angry now, I could tell, though probably few others would have been able to. Like a parent who was 'just disappointed' with a child's choices, he was always at his most dangerous when he went quiet.

He also made his intentions clear with a bombshell of a _lux_ which bounced heavily across the loch before exploding, turning a diametre of about ten metres of water into a cloud of steam.

"Or we could do that," Beverley sighed.

"Sixty seconds," Sahra said, her voice rising with worry.

"Oi," said a voice from the fog.

She was enormous, and confusing, because it surely wasn't possible to be a human and a seal and a snake all at once, and every time you looked at any one part of her you could have sworn it had been different a moment before.

"Do ye nae mind?" she said, scowling under her thatch of thick black hair, the seal spots on her face shifting and roiling. Her accent was so thickly Scottish that it was hard to determine where it was from or whether she was even speaking English rather than some ancient mix of Gaelic. A few metres behind her enormous, coiled body, the beady eyes of smaller selkies were peering at us from the surface, popping up and down into the air, leaving bubbles in their wake. " _You're_ the ones who be trespassing, wizards."

"Ninety seconds," Sahra whispered. She was staring pop-eyed at the queen; beside her, Beverley warily scraped her hair back out of her face.

I tried to remember how long an ordinary person could hold their breath under water. Wasn't it about three minutes or so before brain damage? But that was under ideal circumstances, and it was unlikely Walid had had a full lungful when he was dragged down.

"We meant no disrespect to your waters," Nightingale said clearly. He was standing now, his staff held tightly in one hand. "We ask that you release my companion."

The queen grinned nastily, her whiskers and tail lazily unfurling. "To excuse trespass demands tribute."

"Surely," Nightingale tried, a grim smile on his face, "you would prefer something more official."

"Oh, he'll do," she said, halfway between smug and dismissive. "He's a local lad, we've fed on them for thousands of years. Quite used to the taste. Besides," she said, her black eyes narrowing greedily on Nightingale's staff, "I would demand more."

"Peter," Nightingale said. He turned slightly towards where I was still slumped like a dead fish on the dock. "What's that horrid phrase the Force keeps bandying about concerning terrorists?"

"Uh," I said, slightly nonplussed. "That we don't negotiate with them?"

"Quite so," Nightingale nodded, and then he ignited another _lux_ in his hand, this one bright and pulsing and clearly itching to be released; the queen hissed through her teeth, and the water boiled around her.

"I am not t'be trifled with, wizard," she spat. In one surging movement, the long muscled lines of her body pushed her through the water to within a few feet of the dock; I am not ashamed to admit that I might have made an odd squeaking sound as she loomed over Nightingale. "You _will_ return to make redress."

"You have my word on it," Nightingale said calmly, his werelight still revolving over his palm.

"Hmph," she said; she looked disdainfully down at Beverley, who scowled right back, and then, far more quietly than I would have expected, she sank down beneath the water and the surface of the loch shimmered its way into total silence.

"Shit," Sahra breathed, looking at the stopwatch again in the stunned quiet that followed. "Four minutes and twenty seconds."

"Beverley?" Nightingale asked, and Beverley shook her head; she was quickly tying up her hair into a ponytail in preparation to go back under for a look.

Something surfaced thirty feet from the pier: it was Walid, and for the first time that morning he didn't look well. He thrashed and yelled, and looked like he was going to go under again – next to me, Beverley swore under her breath and then, without another word, finally launched herself into the water in a graceful dive which had more of an effect on me than was probably appropriate. Nightingale watched intently as she fetched up beside Walid and started to pull him back, lying in the recovery position against her chest; wisely, he didn't resist, and she was handing him up to Nightingale and Sahra within moments. There was blood across his face and torso, dripping from around his mouth, and the parts of him that were suddenly exposed to the frigid air were turning an alarming shade of lobster pink as he coughed up water and what looked like bits of kelp onto the pier.

"Car, now," Nightingale said brusquely, and he and Sahra each got an arm under one of Dr Walid's and rapidly rushed him away. You could tell it was serious when Nightingale bundled him into the back seat of the Jag without a care for the upholstery; I, meanwhile, still trying to catch my breath, leaned over the edge of the pier to help Beverley out, only to find her floating peacefully, face-up and smiling with bliss.

"Uh, Bev," I said. "We've got a bit of an emergency."

"Oh, but it's so nice," she said dreamily. "Every single one of my pores has cleared."

"I'll take you on a tour of the Lake District next summer, promise. Now can we go?"

The Jag and its occupants had roared off back towards the cottage by the time we had gotten to the end of the pier. Beverley shook herself from end to end like a cat and was decent enough to turn her back and squeeze out her hair while I clumsily got myself out of the top half of the wetsuit and laid towels across the front seats of the Asbo; by the time we eventually got ourselves inside the heater had cranked itself wheezily up to its maximum and my fingers had unfrozen themselves just enough that I could drive, and we made it back to the cottage within fifteen minutes of Walid coming out of the loch, hoping that the fire had been built up again to finish the process of drying us both out.

Despite what I knew of his relationship, it still startled me whenever I came across Nightingale doing something overtly intimate or domestic. Not in a bad way, of course, and I didn't generally think he was incapable of it, but it simply wasn't a part of what I knew of him as my governor. So it struck me as not a little odd, but certainly – sweet? God, I had a problem if I was thinking of my boss as sweet – to come into the sitting room of the cottage to find Nightingale with a fluffy towel in his hands and frowning as he rubbed rapidly at what must have been Dr Walid's head. The rest of Walid was completely invisible, piled beneath what looked like about six different layers of blankets and tartan, and there was a line of hot-water bottles waiting to be used or refreshed on the floor in front of the sofa next to a sodden heap of ripped wetsuit.

Something muffled came out of the pile, and Nightingale paused for a moment. "What?"

"Tea," Walid said, sounding miserable, and Nightingale relented, lifting the towel just long enough for Walid's tousled head to become visible and for him to reach forward to grab a mug of what smelled like oolong from the coffee table. Nightingale only allowed him a mouthful – which I suspected must have been heavily spiked, judging by the half-empty bottle of Oban whiskey that was also sitting innocuously on the table – before he took the cup out of Dr Walid's hand, put it firmly back down, and went briskly about his work again.

I couldn't say I blamed him for being overprotective, because Walid looked terrible. Besides his complete lack of color, I saw in that brief moment that there were nasty rings of bite-marks dotted about his face and collarbones, and a circle of punctures, still bleeding, around his mouth – the selkies must have somehow fed him air to keep him alive underwater, I realized (I mentally added ‘does not metabolize oxygen’ to my list of attributes of the selkie species for the inevitable report I’d be writing later), and none too gently, which sounded even worse than it looked.

"How are you?" I asked, as I sat gingerly down in front of what was once again a full fireplace; Sahra came in from the kitchen with another full kettle of boiling water and a trayful of mugs as Beverley sat next to me and we gratefully let the heat wash over us both.

"He should be in hospital," Nightingale said sternly.

"I'm cold, not dead," Walid protested from under the tartan.

"You're in a high-risk group for pneumonia regardless."

"I'm fifty-six, _not dead_ ," Walid huffed.

I made a face; the wetsuit was getting clammy and heavy around my legs. "What do you reckon we're going to do about the queen, sir?"

"Hard to tell," Nightingale said, frowning. "We shall certainly have to return. Under what circumstances, I'm not sure."

"I don't know how much I'll be able to help," Beverley said, smiling briefly up at Sahra as she accepted a cup of tea. "I get the feeling they weren't very impressed by my negotiating style."

"Not surprised," I muttered, and clearly didn't sound enough like I had been joking, because the flick she gave my ear in response hurt quite a lot.

"We've got nothing to negotiate _with_ ," Nightingale said in frustration. "I'm hardly going to conclude an agreement on the terms they've already offered."

"You’re not going to what?"

It was Walid, who had pulled the towel off of his head; he was looking, if it was possible, even peakier than before, with growing flushes of unhealthy heat in his cheeks. "What agreement?"

"The agreement which keeps you from being eaten," Beverley said, and I nudged her, hard, to shut her up, because the stricken look on Walid's face was suddenly being matched by one of severe trepidation on Nightingale's, and neither of those things seemed right.

"Peter," Nightingale said quietly. "As much as I hate to deprive either of you of the fire – would you all mind giving us a moment?"

"Uh," I said, and then rapidly stood, pulling Beverley up with me despite her wordless sound of protest. "Sure. No problem."

I grabbed a couple of blankets from the inexhaustible pile out of a handsome wooden chest next to the doorway, and, once I had gotten it closed behind us all, took a moment to drape them over as much of me as they could cover as I huddled up against the completely inadequate gas heater in the front corridor; I would have resolutely stayed there, had I not gotten a bit distracted by my companions.

"What are you two doing?"

They'd both piled themselves up against the door to the sitting room, Beverley with her ear pressed to it and Sahra below her, peering through the keyhole. In that brief, glorious moment, I found myself wishing beyond anything that I'd had a camera on me.

"Oh, sure," Beverley whispered. "You go ahead and _try_ to tell me you're not interested in your governor having a row with his husband."

"You know what," I said, indignantly, " – move over, fuck's sake."

By the time we had all scuffled our way into a new arrangement we had missed the beginning of the conversation, but what continued didn't sound like it was following a good beginning.

" – had no notion. I was a bit busy worrying about breathing. But if I had been aware, I can assure you I wouldn't have let you promise anything on my account."

"The circumstances demanded – "

"There shouldn't have _been_ any circumstances, and that is my fault. I should have recommended you bring a qualified assistant."

"You're qualified."

"I'm _compromised_ , Thomas," Walid said, his voice rising slightly. "The oath I swore to you included protecting you against my being in danger. This wasn't supposed to happen again."

Below me, Sahra looked at Beverley, and Beverley mouthed something that looked like _Goblin_ , and then shook her head to indicate she'd spill those beans later.

"This isn't a zero-sum game, Abdul," Nightingale was saying then. "I won't let you accept all the blame. Whatever mistakes we've made to lead to this moment, I have accepted the consequences. And whatever price I’ll pay will have been worth it."

Walid sighed, and there was the creak of the sofa shifting. "We agreed we wouldn't be made pawns against each other."

"We agreed to try. There's a difference." Another pause. "How are you feeling now?"

"Sore."

"Really?" Nightingale said, and though he hadn't sounded sarcastic there was clearly some inside joke contained in the word, because Walid laughed, which turned into a hacking cough. "Will you feel up to going back to the loch tomorrow morning?"

"I'll have to, won't I," Walid rasped. "The terms have been set."

Beverley twisted beneath me and frowned at Sahra. "You know," she whispered, "even after all these years, I still can't figure out which one's the dom."

"I _know_ ," Sahra said, sounding fascinated.

"File under things you are _not allowed to say about my boss_ ," I hissed.

The handle of the door suddenly clicked under my ear; I had just managed to take a step back when it opened, but Beverley and Sahra weren't so lucky, and flailed their way clumsily upright as Nightingale, his eyebrows raised, looked out at us all.

"Constable Grant," he said sardonically, the touch of distant humor in his eyes telling us that we were – just – forgiven. "I believe we should get back to our books."

We took half an hour to all get settled, after that – I retreated to the bedroom upstairs, managed to finally peel off the remains of my wetsuit, and then followed Beverley in taking an overlong bath in the tiled ensuite, topping it off with freshly hot water every few minutes and blessing the existence, even in the fag-ends of Scotland, of modern plumbing. By the time I came back downstairs it had been decided that Walid, still by the fire, would be taken to A&E at the nearby Lorn and Islands Hospital if the thermometer in his first-aid kit showed his temperature had risen anywhere close to 39, and Nightingale, Beverley, and Sahra were gathered around the piles of Folly reference texts and printouts I had gathered and brought with us from London.

We had, after all, tried to do what research we could before we'd left to come north – the problem was that the corpus of Scottish magical myth was just completely massive, and either ridiculously complicated or hyper-specific to local towns and villages. The fact that selkie and mermaid lore was widespread worldwide didn't help, either, and had left us mostly throwing up our hands and having to wait to see what we would find. Now that we _had_ found what we'd found, though, we would hopefully have more of a chance of narrowing down what our newfound friends were, and what they might want.

It took hours to wade through all the permutations and pseudo-scientific classifications of mermaids alone, before we turned our attention to selkies and their skins; around three in the afternoon, Walid called hoarsely out to us that when it came to the terms and tone of negotiation we had better get up to speed on the honor codes of the Seelie and Unseelie courts, too, which led to me wrestling with the cottage’s frankly woeful WiFi for a good forty-five minutes before I could dive into the depths that was Wikipedia’s collection of pages on British fae.

By that time we had sort of lost Nightingale, because he had – with good reason – become preoccupied with how Walid had spoken less and less often across the course of the early evening, and how by the time we were tiredly scraping together eggs on toast for supper (chased with a selection of the remains of our liquor supply), he had declined into a flushed, hazy stare into the fireplace, sweat beading on his face. He was still scowling at any mention of Lorn & Islands, however, and muttered something rude at one point about disowning anyone who would dare to make any sort of joke along the lines of the physician healing himself. Sahra gave up first, yawning her way to bed; I went up with Beverley shortly thereafter, but not before I’d told Nightingale that I’d drive them both to the A&E whenever he asked. He nodded his distracted thanks, looking caught off guard in a way I’d never quite seen from him before, and switched off the lights in the stairwell in our wake.

I was up early the next morning, and pulled on three layers of jumpers in the chill of our bedroom before heading quietly downstairs. The picture in the sitting room had finally changed; it was Nightingale, now, who was dozing in a wingbacked armchair next to the dying fire, his legs haphazardly crossed, and the sound of a whistling kettle was leaking out from the kitchen beyond. It was a real relief to see Walid on his feet over the stove, messily dressed in fleece and flannel; he still looked a bit tottery and his forehead was still damp, but his color had definitely improved, and he smiled as he heard me coming, holding out a steeping mug of tea for me to take.

“Good morning,” he said, his voice still raw. “I’m sorry to have given you all a scare.”

“I should be thanking you,” I said instead, thinking that our semi-privacy would lend my words some weight. “You did save me from being taken down too, after all.”

“Yes,” he grimaced. “I can’t say it was pleasant. That reminds me – I wasn’t sure where you were keeping your sample bags. Some of our new friends left some teeth behind – in me, I should say – which I wouldn’t mind having analyzed.”

“Bloody hell,” I said numbly. “You _are_ a bit mad, you know.”

“Perhaps,” he grinned. “I’m also sorry, by the way,” he added, his expression deepening into a small frown, “if we gave you any wrong impression of our discussion yesterday.”

“No,” I said quickly. “No, not at all. I think I get it. I can be a right idiot at times, but only when I haven’t thought anyone cared. You do. Care, I mean,” I added lamely, sure he would think me an immature git. “I wouldn’t want anyone to worry over me, either.”

“Well said,” Walid said, after a pause, and I was pretty sure he was amused by me, but was being kind with not showing it. “On to more prescient things – is there a plan of attack?”

There wasn’t, really, but that didn’t mean we weren’t going to try. An hour later everyone in the house was up and dressed, and it was just getting properly light, around eight o’clock, when we arrived back at the loch. Mist was rising gently from the water as we got out of the cars and took up our positions: we’d decided that, as the most obvious aggressors the previous day, Beverley and I would remain at the foot of the pier, on land, while the others went down to the edge. Sahra then stopped about halfway to the end, standing with her feet firmly planted apart and her police baton unfurled in one hand to make it as clear as she could that she was a backup to be feared, while Nightingale and Walid continued on. Just out of our earshot, Nightingale turned to Dr Walid and said something; Walid nodded, and then Nightingale floated his werelight genteelly out over the lake.

It occurred to me that things were not going to go badly, or that they were at least going to go better than I had expected, as soon as one of the selkies joyfully jumped out of the water and batted at the werelight with her head like an exuberant seal playing with a ball.

It was rather like watching something at the theatre, after that. The queen rose out of the water like a medusa; she spoke to Nightingale; they gestured back and forth between each other, clearly bargaining over Walid’s fate given the put-out look on the doctor’s face. At another point the queen loomed over Walid, and then peered at something he pulled out of his coat pocket – all the while, meanwhile, the younger, smaller selkies were leaping and spinning at the surface of the loch as though in a playground, chasing after Nightingale’s werelight as it skipped and bounced amongst them. If the situation hadn’t been so serious, it might have been adorable.

The queen, having apparently satisfied her curiosity about Walid, turned and barked something that sounded half-Gaelic and half-seal at her entourage. There was a stunned silence for a moment, and then one of the selkies swam sullenly up to the pier’s edge; before I really knew what was happening, she was clambering out of the water, a naked, red-haired girl, scowling as she shrugged what looked like a thick, undulating second skin off of her back.

Walid turned back and called to Sahra, who went hurrying forward, shrugging out of her long puffed jacket and rapidly folding it around the girl’s shoulders. Nightingale, meanwhile, was carrying out yet more confused conversation with the queen, who, with a thundering crash, suddenly dived back into the loch, sending a splash of water up just far enough that it crested over Nightingale’s head.

“Oh my god,” Beverley said, and started down the pier, with me at her heels.

Nightingale was spluttering, but otherwise unharmed, as his werelight finally winked out over the water’s surface and the remaining selkies, disappointed, sank away from view. Walid, meanwhile, was efficiently buttoning the selkie girl into Sahra’s coat, her strange mantle of slippery skin folded over his arm.

“You are under no obligation whatsoever, let me be perfectly clear,” he was saying as we approached; the selkie lore from the previous night flooded into my head, reminding me that if the myths were true, she was in effect in thrall to whomever held her pelt. “You can go home this instant if you so desire.”

“Aye,” the girl said throatily. “But I dinnae. Ma says I’ve a head for apothec’ry.”

“Right,” Walid said with a sigh, albeit also with a kind smile on his face. “Peter, Beverley, Sahra – meet Agatha. She’ll be starting at UCL Medical next term.”

“Hi,” Beverley said, fascinated.

“Let’s all get somewhere warmer, shall we?” Nightingale said tightly; he had started to shiver, and, no doubt despite himself, looked thoroughly pathetic. “I’ve had enough fun and games for one trip.”

It emerged, as we closed up the cottage again and Beverley and Sahra cobbled together enough spare clothes to get Agatha fully dressed, that the selkie queen had proved far more amenable to suggestion than any of us had feared at first. The colony was, Nightingale explained as he indulged in a warming few fingers of whiskey, essentially lonely – we should have guessed from the first, he suspected, that there was something important in the fact that all the bite victims we had read about in HOLMES had, in the end, made it home again, and had not been drowned or disemboweled in the loch. The selkies may not have known how to treat a guest, as was evidenced by their rough treatment of Dr Walid, but they had far more of an interest in contact and friendship with the world above the water than in causing harm. The agreement, therefore, that Walid would take Agatha under his wing at university had proved an eminently sensible alternative to demanding tribute in blood for everyone concerned.

Nightingale, Walid, and Agatha were to drive back together in the Jag; as we were all packing up and slamming car doors I found myself unable to resist looking back across the landscape of fields and hills, thinking that somehow, I finally understood the attraction. I was distracted from the view, however, as the Jag started off down the rutted track from the cottage to the road, by a bout of giggling from Sahra and Beverley in the Asbo.

"What's so funny?" I asked as I got in and shut the door behind me, blowing briefly into my chilled hands before switching on the ignition.

"We've decided that Nightingale's the dom," Sahra said matter-of-factly, "but Walid is definitely a power sub. Do you have anything to add?"

“No,” I sighed, knowing resistance was futile, and put the car clunkily into gear.

*

**Author's Note:**

> Walid will always have random music floating around, because I am a Nerd. I only recently discovered that Haydn arranged hundreds(!) of Scottish folk songs, all of which are lovely - the one I had in mind while writing was the first one on [this video](https://www.youtube.com/watch?v=y1S-lhZed4Y). Title from James Thomson's _A Poem Sacred to the Memory of Sir Isaac Newton_ (1727).


End file.
